Cleanup: Moved all l4_ipc_return() calls to uppermost handler routine.

Now all system calls can simply return their final values and they
will be sent to client parties from a single location. Should have had this
simple cleanup a long time ago.

tasks/mm0/include/syscalls.h

@@ -22,8 +22,8 @@ struct sys_mmap_args {
 	off_t offset;
 };
 
-int sys_mmap(l4id_t sender, void *start, size_t length, int prot,
+void *sys_mmap(l4id_t sender, void *start, size_t length, int prot,
-	     int flags, int fd, off_t offset);
+	       int flags, int fd, off_t offset);
 
 int sys_munmap(l4id_t sender, void *vaddr, unsigned long size);
 

tasks/mm0/include/utcb.h

@@ -8,7 +8,7 @@ int utcb_pool_init(void);
 
 
 /* IPC to send utcb address information to tasks */
-int task_send_utcb_address(l4id_t sender, l4id_t taskid);
+void *task_send_utcb_address(l4id_t sender, l4id_t taskid);
 
 /* Prefault an *mmaped* utcb */
 int utcb_prefault(struct tcb *task, unsigned int vmflags);

tasks/mm0/main.c

@@ -28,12 +28,12 @@ void handle_requests(void)
 	u32 mr[MR_UNUSED_TOTAL];
 	l4id_t sender;
 	u32 tag;
-	int err;
+	int ret;
 
 	// printf("%s: Initiating ipc.\n", __TASKNAME__);
-	if ((err = l4_receive(L4_ANYTHREAD)) < 0) {
+	if ((ret = l4_receive(L4_ANYTHREAD)) < 0) {
 		printf("%s: %s: IPC Error: %d. Quitting...\n", __TASKNAME__,
-		       __FUNCTION__, err);
+		       __FUNCTION__, ret);
 		BUG();
 	}
 
@@ -47,85 +47,82 @@ void handle_requests(void)
 
 	switch(tag) {
 	case L4_IPC_TAG_WAIT:
-	 	/*
-		 * A thread that wants to sync with us would have
-		 * started here.
-		 */
 		// printf("%s: Synced with waiting thread.\n", __TASKNAME__);
-		break;
+		/* This has no receive phase */
+		return;
 
 	case L4_IPC_TAG_PFAULT:
 		/* Handle page fault. */
-		page_fault_handler(sender, (fault_kdata_t *)&mr[0]);
+		ret = page_fault_handler(sender, (fault_kdata_t *)&mr[0]);
 		break;
 
 	case L4_IPC_TAG_TASKDATA:
 		/* Send runnable task information to fs0 */
-		send_task_data(sender);
+		ret = send_task_data(sender);
 		break;
 
 	case L4_IPC_TAG_SHMGET: {
 		struct sys_shmget_args *args = (struct sys_shmget_args *)&mr[0];
-		sys_shmget(args->key, args->size, args->shmflg);
+		ret = sys_shmget(args->key, args->size, args->shmflg);
 		break;
 	}
 
 	case L4_IPC_TAG_SHMAT: {
 		struct sys_shmat_args *args = (struct sys_shmat_args *)&mr[0];
-		sys_shmat(sender, args->shmid, args->shmaddr, args->shmflg);
+		ret = (int)sys_shmat(sender, args->shmid, args->shmaddr, args->shmflg);
 		break;
 	}
 
 	case L4_IPC_TAG_SHMDT:
-		sys_shmdt(sender, (void *)mr[0]);
+		ret = sys_shmdt(sender, (void *)mr[0]);
 		break;
 
 	case L4_IPC_TAG_UTCB:
-		task_send_utcb_address(sender, (l4id_t)mr[0]);
+		ret = (int)task_send_utcb_address(sender, (l4id_t)mr[0]);
 		break;
 
 	case L4_IPC_TAG_READ:
-		sys_read(sender, (int)mr[0], (void *)mr[1], (int)mr[2]);
+		ret = sys_read(sender, (int)mr[0], (void *)mr[1], (int)mr[2]);
 		break;
 
 	case L4_IPC_TAG_WRITE:
-		sys_write(sender, (int)mr[0], (void *)mr[1], (int)mr[2]);
+		ret = sys_write(sender, (int)mr[0], (void *)mr[1], (int)mr[2]);
 		break;
 
 	case L4_IPC_TAG_CLOSE:
-		sys_close(sender, (int)mr[0]);
+		ret = sys_close(sender, (int)mr[0]);
 		break;
 
 	case L4_IPC_TAG_FSYNC:
-		sys_fsync(sender, (int)mr[0]);
+		ret = sys_fsync(sender, (int)mr[0]);
 		break;
 
 	case L4_IPC_TAG_LSEEK:
-		sys_lseek(sender, (int)mr[0], (off_t)mr[1], (int)mr[2]);
+		ret = sys_lseek(sender, (int)mr[0], (off_t)mr[1], (int)mr[2]);
 		break;
 
 	case L4_IPC_TAG_MMAP2: {
 		struct sys_mmap_args *args = (struct sys_mmap_args *)mr[0];
-		sys_mmap(sender, args->start, args->length, args->prot,
+		ret = (int)sys_mmap(sender, args->start, args->length, args->prot,
 			 args->flags, args->fd, args->offset);
 	}
 	case L4_IPC_TAG_MMAP: {
 		struct sys_mmap_args *args = (struct sys_mmap_args *)&mr[0];
-		sys_mmap(sender, args->start, args->length, args->prot,
+		ret = (int)sys_mmap(sender, args->start, args->length, args->prot,
 			 args->flags, args->fd, __pfn(args->offset));
 		break;
 	}
 	case L4_IPC_TAG_FORK: {
-		sys_fork(sender);
+		ret = sys_fork(sender);
 		break;
 	}
 	case L4_IPC_TAG_BRK: {
-//		sys_brk(sender, (void *)mr[0]);
+//		ret = sys_brk(sender, (void *)mr[0]);
 //		break;
 	}
 
 	case L4_IPC_TAG_MUNMAP: {
-		sys_munmap(sender, (void *)mr[0], (unsigned long)mr[1]);
+		ret = sys_munmap(sender, (void *)mr[0], (unsigned long)mr[1]);
 		break;
 	}
 	case L4_IPC_TAG_MSYNC: {
@@ -141,6 +138,12 @@ void handle_requests(void)
 		       read_mr(1), read_mr(2), read_mr(3), read_mr(4),
 		       read_mr(5));
 	}
+
+	/* Reply */
+	if ((ret = l4_ipc_return(ret)) < 0) {
+		printf("%s: L4 IPC Error: %d.\n", __FUNCTION__, ret);
+		BUG();
+	}
 }
 
 #if 0

tasks/mm0/src/clone.c

@@ -10,6 +10,7 @@
 #include <l4lib/arch/syslib.h>
 #include <l4lib/ipcdefs.h>
 #include <l4lib/exregs.h>
+#include <l4/api/errno.h>
 #include <l4/api/thread.h>
 #include <utcb.h>
 #include <shm.h>
@@ -68,10 +69,8 @@ int do_fork(struct tcb *parent)
 	 * kernel stack and kernel-side tcb copied
 	 */
 	if (IS_ERR(child = task_create(parent, &ids, THREAD_COPY_SPACE,
-			    	       TCB_NO_SHARING))) {
+			    	       TCB_NO_SHARING)))
-		l4_ipc_return((int)child);
+		return (int)child;
-		return 0;
-	}
 
 	/* Set child's fork return value to 0 */
 	memset(&exregs, 0, sizeof(exregs));
@@ -87,10 +86,9 @@ int do_fork(struct tcb *parent)
 	 * available for child to shmat()
 	 */
 	if (IS_ERR(utcb_shm = shm_new((key_t)child->utcb,
-				      __pfn(DEFAULT_UTCB_SIZE)))) {
+				      __pfn(DEFAULT_UTCB_SIZE))))
-		l4_ipc_return((int)utcb_shm);
+		return (int)utcb_shm;
-		return 0;
+
-	}
 	/* FIXME: Should we munmap() parent's utcb page from child? */
 
 	/*
@@ -105,26 +103,24 @@ int do_fork(struct tcb *parent)
 	/* Add child to global task list */
 	task_add_global(child);
 
-	printf("%s/%s: Starting forked child.\n", __TASKNAME__, __FUNCTION__);
 	/* Start forked child. */
+	printf("%s/%s: Starting forked child.\n", __TASKNAME__, __FUNCTION__);
 	l4_thread_control(THREAD_RUN, &ids);
 
-	/* Return back to parent */
+	/* Return child tid to parent */
-	l4_ipc_return(child->tid);
+	return child->tid;
-
-	return 0;
 }
 
 int sys_fork(l4id_t sender)
 {
 	struct tcb *parent;
 
-	BUG_ON(!(parent = find_task(sender)));
+	if (!(parent = find_task(sender)))
+		return -ESRCH;
 
 	return do_fork(parent);
 }
 
-
 int sys_clone(l4id_t sender, void *child_stack, unsigned int flags)
 {
 	struct task_ids ids;
@@ -138,10 +134,8 @@ int sys_clone(l4id_t sender, void *child_stack, unsigned int flags)
 	ids.tgid = parent->tgid;
 
 	if (IS_ERR(child = task_create(parent, &ids, THREAD_SAME_SPACE,
-			    	       TCB_SHARED_VM | TCB_SHARED_FILES))) {
+			    	       TCB_SHARED_VM | TCB_SHARED_FILES)))
-		l4_ipc_return((int)child);
+		return (int)child;
-		return 0;
-	}
 
 	/* Allocate a unique utcb address for child */
 	child->utcb = utcb_vaddr_new();
@@ -151,10 +145,8 @@ int sys_clone(l4id_t sender, void *child_stack, unsigned int flags)
 	 * available for child to shmat()
 	 */
 	if (IS_ERR(utcb_shm = shm_new((key_t)child->utcb,
-				      __pfn(DEFAULT_UTCB_SIZE)))) {
+				      __pfn(DEFAULT_UTCB_SIZE))))
-		l4_ipc_return((int)utcb_shm);
+		return (int)utcb_shm;
-		return 0;
-	}
 
 	/* Map and prefault child's utcb to vfs task */
 	task_map_prefault_utcb(find_task(VFS_TID), child);
@@ -169,14 +161,12 @@ int sys_clone(l4id_t sender, void *child_stack, unsigned int flags)
 	/* Add child to global task list */
 	task_add_global(child);
 
-	printf("%s/%s: Starting forked child.\n", __TASKNAME__, __FUNCTION__);
 	/* Start forked child. */
+	printf("%s/%s: Starting forked child.\n", __TASKNAME__, __FUNCTION__);
 	l4_thread_control(THREAD_RUN, &ids);
 
-	/* Return back to parent */
+	/* Return child tid to parent */
-	l4_ipc_return(child->tid);
+	return child->tid;
-
-	return 0;
 }
 
 

tasks/mm0/src/fault.c

@@ -711,8 +711,7 @@ int page_fault_handler(l4id_t sender, fault_kdata_t *fkdata)
 	 * FIXME: We could kill the thread if there was an error???
 	 * Perhaps via a kill message to kernel?
 	 */
-	l4_ipc_return(err);
+	return err;
-	return 0;
 }
 
 /* Checks if an address range is a validly mapped area for a task */

tasks/mm0/src/file.c

@@ -405,45 +405,29 @@ int do_close(struct tcb *task, int fd)
 
 int sys_close(l4id_t sender, int fd)
 {
-	int retval;
+	int ret;
 	struct tcb *task;
 
-	if (!(task = find_task(sender))) {
+	if (!(task = find_task(sender)))
-		l4_ipc_return(-ESRCH);
+		return -ESRCH;
-		return 0;
-	}
 
 	/* Sync the file and update stats */
-	if ((retval = fsync_common(task, fd)) < 0) {
+	if ((ret = fsync_common(task, fd)) < 0)
-		l4_ipc_return(retval);
+		return ret;
-		return 0;
-	}
 
 	/* Close the file descriptor. */
-	retval = do_close(task, fd);
+	return do_close(task, fd);
-	printf("%s: Closed fd %d. Returning %d\n",
-	       __TASKNAME__, fd, retval);
-	l4_ipc_return(retval);
-
-	return 0;
 }
 
 int sys_fsync(l4id_t sender, int fd)
 {
 	struct tcb *task;
-	int ret;
 
-	if (!(task = find_task(sender))) {
+	if (!(task = find_task(sender)))
-		ret = -ESRCH;
+		return -ESRCH;
-		goto out;
-	}
 
 	/* Sync the file and update stats */
-	ret = fsync_common(task, fd);
+	return fsync_common(task, fd);
-
-out:
-	l4_ipc_return(ret);
-	return 0;
 }
 
 /* FIXME: Add error handling to this */
@@ -610,40 +594,33 @@ int sys_read(l4id_t sender, int fd, void *buf, int count)
 	struct tcb *task;
 	int ret = 0;
 
-	if (!(task = find_task(sender))) {
+	if (!(task = find_task(sender)))
-		ret = -ESRCH;
+		return -ESRCH;
-		goto out;
-	}
 
 	/* Check fd validity */
 	if (!task->files->fd[fd].vmfile)
 		if ((ret = file_open(task, fd)) < 0)
-			goto out;
+			return ret;
 
 
 	/* Check count validity */
-	if (count < 0) {
+	if (count < 0)
-		ret = -EINVAL;
+		return -EINVAL;
-		goto out;
+	else if (!count)
-	} else if (!count) {
+		return 0;
-		ret = 0;
-		goto out;
-	}
 
 	/* Check user buffer validity. */
 	if ((ret = validate_task_range(task, (unsigned long)buf,
 				       (unsigned long)(buf + count),
 				       VM_READ)) < 0)
-		goto out;
+		return ret;
 
 	vmfile = task->files->fd[fd].vmfile;
 	cursor = task->files->fd[fd].cursor;
 
 	/* If cursor is beyond file end, simply return 0 */
-	if (cursor >= vmfile->length) {
+	if (cursor >= vmfile->length)
-		ret = 0;
+		return 0;
-		goto out;
-	}
 
 	/* Start and end pages expected to be read by user */
 	pfn_start = __pfn(cursor);
@@ -659,25 +636,20 @@ int sys_read(l4id_t sender, int fd, void *buf, int count)
 
 	/* Read the page range into the cache from file */
 	if ((ret = read_file_pages(vmfile, pfn_start, pfn_end)) < 0)
-		goto out;
+		return ret;
 
 	/* The offset of cursor on first page */
 	byte_offset = PAGE_MASK & cursor;
 
 	/* Read it into the user buffer from the cache */
 	if ((count = read_cache_pages(vmfile, task, buf, pfn_start, pfn_end,
-				      byte_offset, count)) < 0) {
+				      byte_offset, count)) < 0)
-		ret = count;
+		return count;
-		goto out;
-	}
 
 	/* Update cursor on success */
 	task->files->fd[fd].cursor += count;
-	ret = count;
 
-out:
+	return count;
-	l4_ipc_return(ret);
-	return 0;
 }
 
 /* FIXME:
@@ -696,30 +668,26 @@ int sys_write(l4id_t sender, int fd, void *buf, int count)
 	struct tcb *task;
 	int ret = 0;
 
-	if (!(task = find_task(sender))) {
+	if (!(task = find_task(sender)))
-		ret = -ESRCH;
+		return -ESRCH;
-		goto out;
-	}
 
 	/* Check fd validity */
 	if (!task->files->fd[fd].vmfile)
 		if ((ret = file_open(task, fd)) < 0)
-			goto out;
+			return ret;
 
 	/* Check count validity */
-	if (count < 0) {
+	if (count < 0)
-		ret = -EINVAL;
+		return -EINVAL;
-		goto out;
+	else if (!count)
-	} else if (!count) {
+		return 0;
-		ret = 0;
+
-		goto out;
-	}
 
 	/* Check user buffer validity. */
 	if ((ret = validate_task_range(task, (unsigned long)buf,
 				       (unsigned long)(buf + count),
 				       VM_WRITE | VM_READ)) < 0)
-		goto out;
+		return ret;
 
 	vmfile = task->files->fd[fd].vmfile;
 	cursor = task->files->fd[fd].cursor;
@@ -769,11 +737,11 @@ int sys_write(l4id_t sender, int fd, void *buf, int count)
 	 * Read in the portion that's already part of the file.
 	 */
 	if ((ret = read_file_pages(vmfile, pfn_fstart, pfn_fend)) < 0)
-		goto out;
+		return ret;
 
 	/* Create new pages for the part that's new in the file */
 	if ((ret = new_file_pages(vmfile, pfn_nstart, pfn_nend)) < 0)
-		goto out;
+		return ret;
 
 	/*
 	 * At this point be it new or existing file pages, all pages
@@ -782,7 +750,7 @@ int sys_write(l4id_t sender, int fd, void *buf, int count)
 	byte_offset = PAGE_MASK & cursor;
 	if ((ret = write_cache_pages(vmfile, task, buf, pfn_wstart,
 				     pfn_wend, byte_offset, count)) < 0)
-		goto out;
+		return ret;
 
 	/*
 	 * Update the file size, and cursor. vfs will be notified
@@ -793,11 +761,8 @@ int sys_write(l4id_t sender, int fd, void *buf, int count)
 		vmfile->length = task->files->fd[fd].cursor + count;
 
 	task->files->fd[fd].cursor += count;
-	ret = count;
 
-out:
+	return count;
-	l4_ipc_return(ret);
-	return 0;
 }
 
 /* FIXME: Check for invalid cursor values. Check for total, sometimes negative. */
@@ -807,21 +772,17 @@ int sys_lseek(l4id_t sender, int fd, off_t offset, int whence)
 	int retval = 0;
 	unsigned long long total, cursor;
 
-	if (!(task = find_task(sender))) {
+	if (!(task = find_task(sender)))
-		retval = -ESRCH;
+		return -ESRCH;
-		goto out;
-	}
 
 	/* Check fd validity */
 	if (!task->files->fd[fd].vmfile)
 		if ((retval = file_open(task, fd)) < 0)
-			goto out;
+			return retval;
 
 	/* Offset validity */
-	if (offset < 0) {
+	if (offset < 0)
-		retval = -EINVAL;
+		return -EINVAL;
-		goto out;
-	}
 
 	switch (whence) {
 	case SEEK_SET:
@@ -848,8 +809,6 @@ int sys_lseek(l4id_t sender, int fd, off_t offset, int whence)
 		break;
 	}
 
-out:
+	return retval;
-	l4_ipc_return(retval);
-	return 0;
 }
 

tasks/mm0/src/mmap.c

@@ -582,8 +582,8 @@ void *do_mmap(struct vm_file *mapfile, unsigned long file_offset,
 }
 
 /* mmap system call implementation */
-int sys_mmap(l4id_t sender, void *start, size_t length, int prot,
+void *sys_mmap(l4id_t sender, void *start, size_t length, int prot,
-	     int flags, int fd, unsigned long pfn)
+	       int flags, int fd, unsigned long pfn)
 {
 	unsigned long npages = __pfn(page_align_up(length));
 	unsigned long base = (unsigned long)start;
@@ -593,21 +593,21 @@ int sys_mmap(l4id_t sender, void *start, size_t length, int prot,
 	int err;
 
 	if (!(task = find_task(sender)))
-		return -ESRCH;
+		return PTR_ERR(-ESRCH);
 
 	/* Check fd validity */
 	if (!(flags & MAP_ANONYMOUS))
 		if (!task->files->fd[fd].vmfile)
 			if ((err = file_open(task, fd)) < 0)
-				return err;
+				return PTR_ERR(err);
 
 	if (base < task->start || base >= task->end)
-		return -EINVAL;
+		return PTR_ERR(-EINVAL);
 
 	/* Exclude task's stack, text and data from mmappable area in task's space */
 	if (base < task->map_start || base >= task->map_end || !base) {
 		if (flags & MAP_FIXED)	/* Its fixed, we cannot satisfy it */
-			return -EINVAL;
+			return PTR_ERR(-EINVAL);
 		else
 			start = 0;
 	}
@@ -643,10 +643,7 @@ int sys_mmap(l4id_t sender, void *start, size_t length, int prot,
 	if (prot & PROT_EXEC)
 		vmflags |= VM_EXEC;
 
-	start = do_mmap(file, __pfn_to_addr(pfn), task, base, vmflags, npages);
+	return do_mmap(file, __pfn_to_addr(pfn), task, base, vmflags, npages);
-
-	l4_ipc_return((int)start);
-	return 0;
 }
 
 /* Sets the end of data segment for sender */

tasks/mm0/src/shm.c

@@ -106,35 +106,31 @@ static void *do_shmat(struct vm_file *shm_file, void *shm_addr, int shmflg,
 	return shm->shm_addr;
 }
 
-int sys_shmat(l4id_t requester, l4id_t shmid, void *shmaddr, int shmflg)
+/* TODO: Do we need this?
+ * MM0 never needs a task's utcb page. vfs needs it.
+ * UTCBs get special treatment here. If the task
+ * is attaching to its utcb, mm0 prefaults it so
+ * that it can access it later on whether or not
+ * the task makes a syscall to mm0 without first
+ * faulting the utcb.
+ */
+/*
+	if ((unsigned long)shmaddr == task->utcb_address)
+		utcb_prefault(task, VM_READ | VM_WRITE);
+*/
+
+void *sys_shmat(l4id_t requester, l4id_t shmid, void *shmaddr, int shmflg)
 {
 	struct vm_file *shm_file, *n;
 	struct tcb *task = find_task(requester);
 
 	list_for_each_entry_safe(shm_file, n, &shm_file_list, list) {
-		if (shm_file_to_desc(shm_file)->shmid == shmid) {
+		if (shm_file_to_desc(shm_file)->shmid == shmid)
-			shmaddr = do_shmat(shm_file, shmaddr,
+			return do_shmat(shm_file, shmaddr,
-					   shmflg, task);
+					shmflg, task);
-
-			/*
-			 * UTCBs get special treatment here. If the task
-			 * is attaching to its utcb, mm0 prefaults it so
-			 * that it can access it later on whether or not
-			 * the task makes a syscall to mm0 without first
-			 * faulting the utcb.
-			 */
-			/*
-			if ((unsigned long)shmaddr == task->utcb_address)
-				utcb_prefault(task, VM_READ | VM_WRITE);
-			*/
-
-			l4_ipc_return((int)shmaddr);
-			return 0;
-		}
 	}
 
-	l4_ipc_return(-EINVAL);
+	return PTR_ERR(-EINVAL);
-	return 0;
 }
 
 int do_shmdt(struct vm_file *shm, l4id_t tid)
@@ -164,16 +160,14 @@ int sys_shmdt(l4id_t requester, const void *shmaddr)
 
 	list_for_each_entry_safe(shm_file, n, &shm_file_list, list) {
 		if (shm_file_to_desc(shm_file)->shm_addr == shmaddr) {
-			if ((err = do_shmdt(shm_file, requester) < 0)) {
+			if ((err = do_shmdt(shm_file, requester) < 0))
-				l4_ipc_return(err);
+				return err;
-				return 0;
+			else
-			} else
 				break;
 		}
 	}
 
-	l4_ipc_return(-EINVAL);
+	return -EINVAL;
-	return 0;
 }
 
 
@@ -248,10 +242,8 @@ int sys_shmget(key_t key, int size, int shmflg)
 	struct vm_file *shm;
 
 	/* First check argument validity */
-	if (npages > SHM_SHMMAX || npages < SHM_SHMMIN) {
+	if (npages > SHM_SHMMAX || npages < SHM_SHMMIN)
-		l4_ipc_return(-EINVAL);
+		return -EINVAL;
-		return 0;
-	}
 
 	/*
 	 * IPC_PRIVATE means create a no-key shm area, i.e. private to this
@@ -260,10 +252,9 @@ int sys_shmget(key_t key, int size, int shmflg)
 	if (key == IPC_PRIVATE) {
 		key = -1;		/* Our meaning of no key */
 		if (!(shm = shm_new(key, npages)))
-			l4_ipc_return(-ENOSPC);
+			return -ENOSPC;
 		else
-			l4_ipc_return(shm_file_to_desc(shm)->shmid);
+			return shm_file_to_desc(shm)->shmid;
-		return 0;
 	}
 
 	list_for_each_entry(shm, &shm_file_list, list) {
@@ -275,26 +266,23 @@ int sys_shmget(key_t key, int size, int shmflg)
 			 * on an existing key should fail.
 			 */
 			if ((shmflg & IPC_CREAT) && (shmflg & IPC_EXCL))
-				l4_ipc_return(-EEXIST);
+				return -EEXIST;
 			else
 				/* Found it but do we have a size problem? */
 				if (shm_desc->npages < npages)
-					l4_ipc_return(-EINVAL);
+					return -EINVAL;
 				else /* Return shmid of the existing key */
-					l4_ipc_return(shm_desc->shmid);
+					return shm_desc->shmid;
-			return 0;
 		}
 	}
 
 	/* Key doesn't exist and create is set, so we create */
 	if (shmflg & IPC_CREAT)
 		if (!(shm = shm_new(key, npages)))
-			l4_ipc_return(-ENOSPC);
+			return -ENOSPC;
 		else
-			l4_ipc_return(shm_file_to_desc(shm)->shmid);
+			return shm_file_to_desc(shm)->shmid;
 	else	/* Key doesn't exist, yet create isn't set, its an -ENOENT */
-		l4_ipc_return(-ENOENT);
+		return -ENOENT;
-
-	return 0;
 }
 

tasks/mm0/src/task.c

@@ -438,7 +438,7 @@ void task_map_prefault_utcb(struct tcb *mapper, struct tcb *owner)
  */
 int send_task_data(l4id_t requester)
 {
-	int li = 0, err;
+	int li = 0;
 	struct tcb *t, *vfs, *self;
 	struct task_data_head *tdata_head;
 
@@ -474,12 +474,6 @@ int send_task_data(l4id_t requester)
 		li++;
 	}
 
-	/* Reply */
-	if ((err = l4_ipc_return(0)) < 0) {
-		printf("%s: L4 IPC Error: %d.\n", __FUNCTION__, err);
-		BUG();
-	}
-
 	return 0;
 }
 

tasks/mm0/src/utcb.c

@@ -39,7 +39,7 @@ void *utcb_vaddr_new(void)
  * for its own. The requester then uses this address as a shm key and
  * maps its own utcb via shmget/shmat.
  */
-int task_send_utcb_address(l4id_t sender, l4id_t taskid)
+void *task_send_utcb_address(l4id_t sender, l4id_t taskid)
 {
 	struct tcb *task = find_task(taskid);
 
@@ -53,7 +53,7 @@ int task_send_utcb_address(l4id_t sender, l4id_t taskid)
 		BUG_ON(!task->utcb);
 
 		/* Return it to requester */
-		return l4_ipc_return((int)task->utcb);
+		return task->utcb;
 
 	/* A task is asking for someone else's utcb */
 	} else {
@@ -64,7 +64,7 @@ int task_send_utcb_address(l4id_t sender, l4id_t taskid)
 			 * none allocated so far, requester gets 0. We don't
 			 * allocate one here.
 			 */
-			return l4_ipc_return((int)task->utcb);
+			return task->utcb;
 		}
 	}
 	return 0;